Shorts ripped top to bottom

I was walking the dog one day last week when I could feel a draft behind me.

I'd heard a quiet 'rip' when I sat down to put my shoes on but when I stood up I felt up and down the seam of my shorts, all was intact, so I ignored it.

As it turned out, it wasn't the seam that had parted - my shorts had ripped right up along the back pocket, vertically and as I go commando, my left ass cheek was out on view for all to see